1. Field of the Invention
The invention relates to a vacuum cleaner of a detergent injection type with a device for supplying detergent to a cleaning brush and an impeller for discharging air sucked up through the cleaning brush.
2. Description of the Related Art
A conventional vacuum cleaner is shown in FIG. 2 as an example, in which a detergent 33 stored in a detergent container 32 is injected to a brush 31 only by sufficient negative pressure in the brush 31. Thus, it takes a while for the rising of the negative pressure and the starting of a cleaning operation. There have also been problems that when the area to be cleaned is positioned above the elevation of the detergent container the detergent sucking function of the negative pressure is insufficient to draw-out the detergent.
In connection with a positive detergent injection, Japanese Laid-Open Publication 61 68912 (04. 09. 1986) discloses a vacuum cleaner including a motor-movable main body with at least a motor-rotatable brush, containers for storing new and used cleaning agents, a means for supplying new cleaning agent to a floor to be cleaned, and a vacuum picking-up device for withdrawing used cleaning agents from the floor. The cleaning agent supplying means has a supplying pump, which is automatically so controlled by the driving motor in the main body, that the supply rate of the cleaning agents can be kept at a uniform level fixed by the user. This vacuum cleaner has, however, the handicap that it requires a separate pump and includes a plurality of motor-rotatable brushes, so that its construction is intricate.